This page has been validated.
THE SKULL OF REPTILES
33
The Skull of the Cotylosauria
(Figs. 1–9, 12, 13, 16 d, e, 17–24, 25 b, c, 26–29)
Fig. 19. Seymouria haylorensis. Cotylosaur skull: from above. One half natural size, n, nasal; l, lacrimal; pf, prefrontal; pof, postfrontal; fr, frontal; it, intertemporal; st, supratemporal; do, dermoöccipital; t, tabulare.
Fig. 20. Seymouria haylorensis. Skull and pectoral girdle: from the side. One half natural size, pm, premaxilla; m, maxilla; l, lacrimal; n, nasal; pf, prefrontal; j, jugal; po, postorbital; sq, squamosal; qj, quadratojugal; cl, clavicle; ic, interclavicle; sc, scapula; c, coracoid.
But few modifications of the primitive characters of the skull are known in this order. The parietal foramen is absent in one or two
